Catheter



FIG. 1 is a perspective view of the catheter;

FIG. 2 is a front view of the catheter;

FIG. 3 is a back view of the catheter;

FIG. 4 is a right side view of the catheter;

FIG. 5 is a left side view of the catheter;

FIG. 6 is a bottom view of the catheter; and,

FIG. 7 is a top view of the catheter.

I claim the ornamental design for a catheter, as shown and described.